Support dynamic Dag generation for native TypeScript Dags #74335

Description

Once #74036 and #74037 land, a native TypeScript Dag bundle can generate its Dags from a YAML file in the Dag bundle. Editing only the YAML changes the live Dags, and their tasks run without repacking the bundle:

• The Dag processor runs the packed bundle on every parse, so the YAML is read fresh.
• A task of a native Dag runs the .min.mjs named by its dag_rel_path, at the run's bundle version, with no check against the dag_ids recorded at pack time.

import { readFileSync } from "node:fs";
import { parse } from "yaml";
import { Bundle, Dag } from "apache-airflow-ts-sdk";

const config = parse(readFileSync(new URL("./dags.yaml", import.meta.url), "utf-8"));

const bundle = new Bundle();
for (const spec of config.dags) {
  const dag = new Dag(spec.dag_id, { queue: "typescript" });
  // add tasks from spec
  bundle.register(dag);
}
await bundle.serve();

Follow-ups

• Add an e2e case: pack the bundle, add a Dag to the YAML in the Dag bundle, wait for a re-parse, then trigger the new Dag and check that it succeeds.
• Document dynamic Dag generation in the TypeScript SDK native Dag guide:
  • Read the YAML at runtime with fs and import.meta.url. Importing it lets the bundler inline it, which freezes it at pack time.
  • Keep the YAML in the same Dag bundle. airflow-ts-pack also runs the bundle, so the YAML must exist at pack time, or the code must handle it being missing.
  • Generation must be deterministic, and every generated Dag needs the queue that routes to the NodeCoordinator.
  • A YAML change shows up on the next periodic re-parse ([dag_processor] min_file_process_interval). Editing the YAML does not trigger an earlier re-parse.
  • With a versioned Dag bundle, runs keep the YAML of their bundle version. With an unversioned bundle, a running Dag run sees the new YAML, and tasks removed from it end as removed.

Depends on

• Parse native Java Dags and show their source #74036
• Parse native TypeScript Dags with the Node coordinator #74037